Peripheral arterial occlusive disease (blockage in the blood flow to the legs) is a painful and debilitating disease. There are few, if any, effective treatments, other than surgically bypassing the blockage with a graft. This is especially true for advanced vascular disease causing non-healing ulcers on the feet, which frequently results in loss of a limb (amputation). Preliminary evidence suggests that the investigational drug (AS-013) may be effective in healing these ulcers and preventing amputation.